...therapy had fallen - plummeted really -  from grace 2 years prior with the death of Jesse Gelsinger in an... the whole field to a grinding stop and only now, 2 decades later, is it finally back in the limelight...the other hand, have broad tropism in the eye. AAV-2, the first identified serotype and the one used in...reading 1. FDA approves gene therapy for blindness 2. Gene Therapy emerges from disgrace to be the next...expression in non-dividing cells because they remain in episomal form in the cell’s nucleus. But since nothing...hope are many more clinical successes for gene (and cell) therapies. One may wonder why the first AAV-based... providing long-term gene expression in retinal cells - AAV - were becoming available. At the same time...

...level of sensitivity. Figure 2: Steps to purify DNA using a cellulose dipstick. Image: Zou et al., 2018...alkaline lysis plasmid miniprep Starting material: 2 mL bacterial culture Product: plasmid DNA This kit-free...protocol: 1) it solubilizes both DNA and agarose, and 2) it helps DNA stick to the glass. After binding DNA...Academy of Sciences of the United States of America, 76 2, 615-9 . https://doi.org/10.1073/pnas.76.2.615  Zhou...broken out of cells with a solution of salts, detergent, and ball bearings. Then a cellulose dipstick is... kits and typically follow the same principles: cells are lysed, RNAs and proteins are removed to leave... could be digested with restriction enzymes.  Cellulose nucleic acid purification Starting material: plant...

...single RNA-guided endonuclease of a class 2 CRISPR-Cas system." Cell (2015). PubMed PMID: 26422227. Find ...CRISPR/Cas9.  How was Cpf1 found and tested? Class 2 CRISPR systems, including the type II Cas9-based system...employed by class 1 systems. A putative new class 2 nuclease, Cpf1 (CRISPR from Prevotella and Francisella...Find plasmids from this publication at Addgene. 2. Zetsche, Bernd, et al. "Multiplex Gene Editing by CRISPR–Cpf1...orthologs that display cleavage activity in mammalian cells. Like Cas9 nucleases, Cpf1 family members contain...GC-content. After sequencing and searching for cellular RNAs important for Cpf1 function, they found that...the PAM. With this information, they turned to a cell culture system to see if any Cpf1 nucleases would...

...human transcription factors such as PAX7, PAX6, AP-2 alpha and ISLET-1. In addition, we distribute monoclonal... example through the use of less toxic adjuvants; 2) generating complex antibody chips that allow assessment...produced by a single B cell. To create a monoclonal antibody cell line, myeloma cells are fused with activated...activated B cells from the spleen of mice injected with the antigen of interest. The immortalized cells, called...distributing over 3,000 antibodies and associated hybridoma cell lines. The DSHB was created by the National Institute... individually isolated and expanded. The clonal cells are screened to identify hybridoma lines, each producing...

... to DFHBI in the presence of that metabolite (Fig.2). Spinach eventually evolved into Spinach2, a more...PMID: 25713381. PubMed Central PMCID: PMC4364232. 2. Baker, Monya. “RNA imaging in situ”. Nature Methods...emerging environmental pollutants.” Front Chem. 2014; 2: 41. PubMed PMID: 25019067. PubMed Central PMCID: ...biosensors.” TrAC Trends in Analytical Chemistry 27(2):108-117 · February 2008. 11. Svensen, Nina and Jaffrey..., peptides, amino acids, drugs, metal ions, and cells (even pathogenic bacteria). That range is possible... over half a century; the Addgene blog has an excellent primer and tips from experts on FRET techniques... combination of SELEX and fluorescence-activated cell sorting (FACS) of E. coli transformed with aptamer...

...imaging of diverse tissues. Nature Protocols, 17(2), Article 2. https://doi.org/10.1038/s41596-021-00644-9 ...directly from the Zenodo dataset.     Figure 2: Screenshot showing reagent entries with associated...approach for deep phenotyping and spatial analysis of cells in complex tissues. Proceedings of the National ...

...Occupational Classification System  and Wikipedia. 2. Social and computer scientists are overrepresented...international Twitter users were included in the dataset; 2) users not part of a scientific Twitter list were ...scientists on Twitter are male and 40% are female Figure 2. Gender Ratio of Scientists on Twitter. 60% of scientist...tweeted by biologists were: Nature, Sciencemag, Wiley, Cell and Scientific American Figure 4: Top Scientific...

...indicated they wanted to see more negative data (Figure 2.) At the same time, when scientists who support open...is not only housed, but encouraged.    Fig. 2: Results from a survey conducted by Addgene in 2021...detailed methods and image descriptions, a minimum n = 2, and well labeled high- and low-magnification images...gene therapy trials. Human Gene Therapy Methods, 26(2), 71–76. https://doi.org/10.1089/hgtb.2015.040 Initiative...What works well in one cell or neuron type may not work well for a neighboring cell type, even within the...options while AAV8 (82%) and AAV9 (84%) were both excellent at infecting our target neurons (Figure 1). However... conditions (3,5,8), injection titers (1,2), and cell types used for packaging viral particles (6), can...

...is excised from the donor vector.   Figure 2: The Gateway system adopts phage integration into ...our website to search for your favorite gene! STEP 2: Generate an Expression Clone When making the expression...expression construct in only 1 day, as opposed to 2+ days with traditional restriction and ligation cloning...Clon Transgen 4:138. doi:10.4172/2168-9849.1000138 2. Hartley JL. Use of the Gateway System for Protein...the next step is to transform competent E. coli cells and select the positive clones. The entry clone ... expression of the human KRAS gene in mammalian cells. STEP 1: Generate an Entry Clone There are a few...ccdB gene. Since the ccdB product is toxic to the cell, Gateway cloning efficiency can reach >99%. ...

...drastically with lower titers. As you can see in figure 2, the expression from the 5x1011 titer was essentially...roughly 6-fold increase in expression [3, Figure 2]. Note how expression increases exponentially with an increase...international 61.1 (2002): S9-S15. PubMed PMID: 11841606. 2. Schultz BR, Chamberlain JS. Recombinant Adeno-associated...Making contact with a cell Although an individual AAV particle’s ability to infect a cell is dependent on its...construction and the cell it’s infecting, getting these particles to infect cells is also very titer-dependent... particle to infect a cell, it has to come into physical contact with that cell. Since there is a limited...of surface area on each cell, the way to get more AAV in contact with the cell is to increase the AAV ...

...ultracompetent (109 CFU/μg) cells. Primer design Using specific primer design (Figure 2), IVA cloning can be...procedure to be performed using a simple two-step, 2 hr protocol prior to transformation (Figure 1). As... for each type of modification is shown in Figure 2, and is discussed in more detail below. The main requirement...Biotechniques 10.1 (1991): 62-66. PubMed PMID: 2003926. 2. Bubeck, Peter, Monica Winkler, and Wilfried Bautsch...transformation efficiency of the strain: when asking the cell to perform multiple recombination events, all linear...linear fragments need to get into the same cell. For simple cloning requiring just one or two recombination...recombination events, homemade competent cells of 107 CFU/μg are perfectly fine, yet performing multiple modifications...

...various components of the immune system. Figure 2: In-vitro models for immunogenicity prediction of ...drug reaction. This system would somewhat act like a 2-step verification. All approaches have their own limitations...Future Enhancements. Frontiers in drug discovery, 2, 952326. https://doi.org/10.3389/fddsv.2022.952326Joubert...epitopes likely to be presented by T cells to elicit an immune response. T cell epitopes are found in either ...that take place within an antigen-presenting cell like a T cell. It is also not yet possible for these algorithms...traditional 2D assays with immune cell lines or peripheral blood mononuclear cells (PBMC) in 3D models of the...CD4+ or CD8+ T-cells or monocytes. PBMCs can be further differentiated into dentritic cells or macrophages...

... were depositing and requesting each year (Figure 2). We did a similar analysis with CRISPR pooled libraries...different categories (Figure 2C). Note that in Figure 2, the numbers on the X axis refer to distribution and...rather than a cumulative total.    Figure 2: Addgene CRISPR deposit and distribution by function...rapid adoption of new tools, illustrated in Figure 2, and the longevity of tools seen in Figure 3, indicates...As we celebrate twenty years at Addgene, we are sharing stories of our repository’s positive impact on... Sharing this story is a truly special way to celebrate our twentieth anniversary in 2024, and it’s all...

... D, Nerhbass U, Montagnier L, Charneau P. Cell. 2000. 101(2): 173-185. PubMed . Woodchuck Hepatitis Virus...selection. Desfarges S, Ciuffi A. Viruses. 2010. Jan;2(1):111-30. PubMed . Altering the tropism of lentiviral...can use FACS to sort cells expressing GFP and later expand these cells into a cell line. Where does lentivirus...actively dividing cell types whereas standard retroviruses can only infect mitotically active cell types. This... necessary. What cell line should be used in order to produce lentivirus? 293T cells are usually used ...be used to make stable cell lines? Lentiviruses can be used to make stable cell lines in the same manner...infected host cells. When these antibiotics are added to the growth medium of the host cells, they kill ...

...everything just right!  Fig. 2: Goldilocks is actually celebrating a successful ChIP experiment! Image...to (1) run a DNA gel to confirm fragment size and (2)  incubate with RNAse and Proteinase K to purify the...proteins of interest to any DNA they were bound to (2) fragmented the DNA (3) used antibodies to specifically... Process ChIP can be done for either tissues or cells. The process is very similar for both, though tissue...fragmenting the DNA, spin down the samples to remove cell debris, which will collect in a pellet. The supernatant..., these are mostly fairly standard molecular and cell biology techniques. What’s all the fuss? Well, ChIP...will also have to be optimized for both tissue or cell type, amount of protein, and desired fragment length...

...Capsids from Serotypes 1, 2, and 5 Display Differential Efficiency and Cell Tropism after Delivery to ...one of lox2272 sites will now be sandwiched between 2 loxp sites and is excised by Cre (Figure 1). This ...flank the transgenes (non-homologous pairs) (Figure 2.). They found that almost all off-target expression...exercise caution when using them.    Figure 2. Schematic diagram showing the mechanism of spontaneous... Tropism and Axonal Transport of AAV Serotypes 1, 2, 5, 6, 8 and 9 in the Mouse Brain. PLoS ONE 8:e76310...specific cell type rely on transgenic models that express recombinases like Cre or Flp in their cells of interest...entry into the cell (Dudek, AM. 2018).  If the serotype you are using transduces cells that you are not...

.... “A FLEX Switch Targets Channelrhodopsin-2 to Multiple Cell Types for Imaging and Long-Range Circuit ...FLP and Cre for additional control   Figure 2: Expression of a morphological marker (eYFP) and synaptic...PMID: 18614669. PubMed Central PMCID: PMC2593125. 2. Buchholz, F, P O Angrand, and A. Francis Stewart....The FLP Recombinase of the Saccharomyces Cerevisiae 2 Micron Plasmid Attaches Covalently to DNA via a Phosphotyrosyl...specific cell types (populations) within neuronal networks in living animals. To accomplish such cell specific...individual cells. With this technique, a Neuroscientist can see the full dendritic arbor of a single cell with...Cre-mediated possibilities for site specific (and often cell type specific) control of DNA recombination and ...

... analogs such as 2-fluoroadenine (2-FA), organisms with functional APT will convert 2-FA to cytotoxic ...selection of plants undergoing RNAi, and LIIbeta F 1-2 RNAi, which allows assembly of intron-spliced hpRNAs...nucleotides, resulting in death. In the presence of 2-FA, potent gene silencing of APT is required for survival...genes known to be essential for cell growth. Together, this excellent work highlights the importance of...fluorescence-activated cell sorting (FACS). This is not possible in plants outside of limited, single cell protoplast...exquisitely and robustly self-organize at the cellular and multicellular scale.     References Bezanilla M, Perroud...can be found at Addgene that could serve as an excellent start (#22988, #137884). Both vectors allow the...

...Carballosa, et al, (2015) eNeuro, March/April 2015, 2(2) e0001-15.2015. Pubmed. Resources: http://openspim.org...orthogonal-plane fluorescence optical sectioning (OPFOS) (2). Arne Voie, David Burns and Francis Spelman focused...in LSFM. In LSFM the laser light sheet, typically 2-6  microns, illuminates only one thin plane of the...transparent are enabling microscopes to visualize the cellular architecture of whole tissues in 3D with unprecedented... Weber, M. Mickoleit, J. Huisken. (2014) Methods Cell Biol.123, 193-215. Pubmed. W. Spalteholz. (1914)...

...Madison lab found that H2B-GFP expressing cells exhibited a 2-4 fold increase in the number of endogenous...Denham lab made several other small changes creating 2 other versions but these did not surpass GEmCherry2...fluorescence and in-frame fluorescence.  Figure 2: The GEmCherry reporter. Image from Højland Knudsen...introduced the reporter into the cells, you’re ready to edit. These cells are then transfected with several... up, all successfully transfected cells will express RFP while cells containing the reporter gene that...using the RFP:GFP ratio, edited cells can be sorted from unedited cells. In an experiment that targeted...Activity. Frontiers in Cell and Developmental Biology 6: . https://doi.org/10.3389/fcell.2018.00054 Sander...